JP6978865B2 - Fluid control device, fluid control method, and program for fluid control device - Google Patents

Description

The present invention relates to, for example, a fluid control device used for pulse controlling the amount of fluid of various gases in a semiconductor manufacturing device.

For example, in an atomic layer deposition device (ALD (Atomic Layer Deposition)), which is a type of semiconductor film forming device, component gas and steam gas are alternately introduced for a short period of time to realize film formation with a film thickness in angstrom units. Is intended to be done.

Therefore, for example, a mass flow controller that controls the flow rate of various gases introduced into the film forming chamber so that various gases required for forming a film for one atom can be introduced into the film forming chamber. Is driven by pulse control (Patent Document 1).

The mass flow controller driven by such pulse control includes a resistor provided in the flow path, a valve provided on the downstream side of the resistor, an on period for opening the valve, and an off period for closing the valve. It is provided with a control mechanism for alternately repeating the period and the valve. More specifically, the mass flow controller causes gas to flow into the internal volume of the flow path between the resistor and the valve during the off period, charges the gas to a predetermined pressure, and is charged during the on period. Flows the gas charged in the internal volume to the downstream side of the valve.

Further, the valve is provided with a displacement sensor for measuring its own opening degree, and the control mechanism has a gas to which the measured opening degree measured by the displacement sensor flows during the on period. It is configured to perform the opening feedback control of the valve so as to match the set opening corresponding to the flow rate of.

However, as a result of diligent studies by the inventor of the present application, even if the opening feedback control is performed as described above, the flow rate actually flowing to the downstream side of the valve is assumed to be, especially when the pulse width is short. It was found that there was an error with respect to. That is, it is difficult to achieve the flow rate accuracy required for, for example, an atomic layer deposition apparatus only by simple opening feedback.

Special Table 2017-509793

The present invention has been made in view of the above-mentioned problems, and provides a fluid control device capable of achieving higher control accuracy than before with respect to the flow rate or pressure of the fluid passing through the valve during each on period in pulse control. With the goal.

That is, the fluid control device according to the present invention has a resistor provided in the flow path through which the fluid flows, a first valve provided on the downstream side of the resistor in the flow path, and the resistance in the flow path. A pressure sensor provided between the body and the first valve to measure the pressure of the fluid in the internal volume between the resistor and the first valve, and a control mechanism for controlling the first valve. The control mechanism is based on a pulse signal generator that inputs a pulse signal having a predetermined pulse height and a predetermined pulse width to the first valve, and a pressure value measured by the pressure sensor. Then, based on the feedback value calculation unit that calculates the time-integrated value of the pressure drop amount generated in the internal volume as the feedback value during the on period when the first valve is opened, and the deviation between the feedback value and the reference value. A signal correction unit for correcting a pulse signal input from the pulse signal generator to the first valve is provided.

According to the findings found for the first time by the inventor of the present application, the time of the pressure drop amount in the on period is compared with the case where the opening degree of the valve is actually measured and the first valve is pulse-controlled by the opening degree feedback as in the conventional case. It is possible to improve the realized flow rate or pressure control accuracy by feeding back the integrated value and performing pulse control of the first valve.

Further, the time integral value of the pressure drop amount during the on period and the flow rate of the fluid passing through the first valve show good linearity, and are easier to handle as the control amount than the opening degree.

Such control characteristics are obtained in relation to such information and the actual flow rate even if the pressure on the upstream side of the first valve fluctuates when the opening is fed back. While the value is not fed back and an error occurs, if it is a time integral value of the pressure drop amount, it is a value related to the actual flow rate, so the generated flow rate error is fed back. It is thought that this is because it can be corrected.

In order to maintain the target flow rate as much as possible in each on period, the reference value is the actual value of the time integral value of the pressure drop amount when the flow rate of the fluid passing through the first valve becomes the target flow rate. It should be.

For example, in order to make the flow rate of the fluid flowing when each pulse is input constant and to make the generated film thickness constant without changing the time until the recipe is completed in ALD or the like. The signal correction unit may be configured to change the pulse height while keeping the pulse width of the pulse signal constant so that the deviation between the feedback value and the reference value becomes small. With such a case, it is possible to realize high-quality film formation while maintaining the number of processes per unit time by setting the time required for the film formation process as scheduled.

As another control mode for keeping the flow rate or pressure of the fluid passing through the first valve constant during each on period, the signal correction unit makes the deviation between the feedback value and the reference value small. Examples thereof include those configured to change the pulse width while keeping the pulse height of the pulse signal constant.

The pressure of the fluid at the internal volume on the upstream side of the first valve is maintained at a predetermined pressure before the start of each on period, and the fluid passes through the first valve during each on period. In order to make the fluctuation of the flow rate or the pressure less likely to occur, the resistor is a second valve whose opening degree can be controlled, and the pressure is in the off period when the control mechanism closes the first valve. It may be further provided with a second valve control unit that controls the second valve so that the deviation between the pressure value measured by the sensor and the set pressure value becomes small. In addition, if it is such a thing, the time integral value of the pressure drop will show high linearity for a wider flow rate range, so it is possible to take a wide control range with only one calibration curve. Will be.

In order to be able to monitor whether or not the first valve is operating as expected by pulse control, if the first valve is further equipped with a displacement sensor for measuring its opening degree. good.

As another aspect of the fluid control device according to the present invention, a second valve which is a resistor provided in the flow path through which the fluid flows and a first valve provided in the flow path on the downstream side of the resistor. A pressure sensor provided between the resistor and the first valve in the flow path and measuring the pressure of the fluid in the internal volume between the resistor and the first valve, and the first valve. The first valve further comprises a displacement sensor for measuring the opening degree of the first valve, and the control mechanism controls the first valve. During the off period for closing, the second valve control unit that controls the second valve so that the deviation between the pressure value measured by the pressure sensor and the set pressure value becomes smaller, and the first valve are predetermined. The pulse height and the pulse signal generator that inputs the pulse signal having a predetermined pulse width, and the measurement opening measured by the displacement sensor during the on period when the first valve is opened are predetermined. An example includes a signal correction unit that corrects a pulse signal input from the pulse signal generator to the first valve based on a deviation from the set opening degree.

In such a case, the fluid is charged so that the pressure of the internal volume is maintained at a predetermined pressure during the off period even when the first valve is pulse-controlled by the opening feedback. Therefore, the control accuracy of the flow rate or the pressure of the fluid passing through the first valve during the on period can be improved as compared with the conventional case.

A resistor provided in the flow path through which the fluid flows, a first valve provided in the flow path on the downstream side of the resistor, and provided between the resistor and the first valve in the flow path. It is a fluid control method using a fluid control device including a pressure sensor for measuring the pressure of the fluid in the internal volume between the resistor and the first valve, and controls the first valve. A control step includes a pulse signal generation step in which a pulse signal having a predetermined pulse height and a predetermined pulse width is input to the first valve, and a pressure measured by the pressure sensor. Based on the value, the feedback step of calculating the time-integrated value of the pressure drop amount generated in the internal volume during the on period when the first valve is opened as the feedback value, and the deviation between the feedback value and the reference value. If a fluid control method including a signal correction step for correcting a pulse signal input from the pulse signal generator to the first valve after the feedback value is calculated is used, the first is performed by opening feedback. The flow rate or pressure can be controlled with higher accuracy than when the valve is pulse controlled.

In order to obtain the same effect as the fluid control device according to the present invention only by updating the program for the existing fluid control device, the resistor provided in the flow path through which the fluid flows and the flow path are described. A first valve provided on the downstream side of the resistor and an internal volume provided between the resistor and the first valve in the flow path and between the resistor and the first valve. A pressure sensor for measuring the pressure of the fluid, an on period for opening the first valve, and a control mechanism for controlling the first valve are provided, and the control mechanism is predetermined for the computer and the first valve. A fluid control program used in a fluid control device including a pulse signal generator for inputting a pulse signal having a pulse height and a predetermined pulse width, and the pressure value measured by the pressure sensor. Based on the feedback value calculation unit that calculates the time-integrated value of the pressure drop amount generated in the internal volume during the on period when the first valve is opened as the feedback value, and the deviation between the feedback value and the reference value. If a fluid control device program that causes the computer to exert its function as a signal correction unit that corrects the pulse signal input from the pulse signal generator to the first valve after the feedback value is calculated is used. good.

The program for the fluid control device may be electronically distributed or may be stored in a program storage medium such as a CD, DVD, HDD, or flash memory.

As described above, according to the fluid control device according to the present invention, the opening degree of the first valve is pulse-controlled based on the time-integrated value of the pressure drop amount during the on period, so that the opening degree itself is fed back and pulse-controlled. It is possible to improve the control accuracy of the flow rate or pressure of the fluid passing through the first valve during the on period. Therefore, it is possible to accurately supply various gases to the film forming chamber in a required minute amount during each on-period, and it is possible to realize highly accurate film forming in, for example, ALD.

The schematic diagram which shows the fluid control apparatus which concerns on 1st Embodiment of this invention, and the atomic layer deposition apparatus which used this fluid control apparatus. The schematic diagram which shows the hardware and software structure of the fluid control apparatus in 1st Embodiment. The schematic graph which shows the pulse signal input to the 1st valve in 1st Embodiment. The first valve by pulse control in 1st Embodiment, and the schematic graph which shows the pressure change of the fluid in the internal volume, and the time integral value of the pressure drop amount. The flowchart which shows the operation of the fluid control apparatus in 1st Embodiment. The graph which shows the control accuracy of the conventional fluid control apparatus and the fluid control apparatus of 1st Embodiment. The schematic diagram which shows the hardware and software structure of the fluid control apparatus which concerns on 2nd Embodiment of this invention. The flowchart which shows the operation of the fluid control apparatus in 2nd Embodiment. The schematic diagram which shows the hardware and software structure of the fluid control apparatus which concerns on 3rd Embodiment of this invention. The flowchart which shows the operation of the fluid control apparatus in 3rd Embodiment.

<Structure of the first embodiment>
The fluid control device 100 according to the first embodiment of the present invention will be described with reference to FIGS. 1 to 5. As shown in FIG. 1, the fluid control device 100 of the first embodiment intermittently supplies various gases to the film forming chamber CH of the atomic layer deposition device 200 (ALD) by pulse control. The fluid control device 100 is provided in each of a first gas supply flow path L1 and a second gas supply flow path L2 communicating with the film forming chamber CH. The first gas supply flow path L1 is for supplying a component gas such as TMA called a precursor into the film forming chamber CH, and the second gas supply flow path L2 is for supplying, for example, water vapor gas to the film forming chamber CH. This is for supplying into the chamber CH.

The pulse control timings of the fluid control devices 100 provided in the first gas supply flow path L1 and the second gas supply flow path L2 are staggered, and the component gas and the steam gas alternate in the film forming chamber CH. Supply to. Further, each fluid control device 100 is configured to supply various gases having a flow rate necessary and sufficient for forming a layer having a thickness of one atom in the film forming chamber CH by one pulse.

Since each fluid control device 100 has substantially the same configuration, the details of one fluid control device 100 will be described below with reference to FIG. 2.

The fluid control device 100 is provided with a resistor 1, a pressure sensor 2, and a first valve 3 in order from the upstream side with respect to the flow path, and further, the first valve 3 is provided based on the output of the pressure sensor 2. It is provided with a control mechanism C for pulse control.

The resistor 1 is, for example, an orifice or the like that generates flow path resistance in the flow path. In the first embodiment, the inner diameter of the orifice is fixed, and the flow path resistance is fixed.

The pressure sensor 2 measures the pressure of a fluid having an internal volume 5 which is a portion between the resistor 1 and the first valve 3 in the flow path.

The first valve 3 is configured such that the valve body is driven by, for example, a piezo actuator, and the opening degree, which is a gap between the valve body and the valve material, can be changed. The first valve 3 further incorporates a displacement sensor 4 so that the displacement amount of the valve body can be measured and the opening degree can be measured.

The control mechanism C controls the first valve 3, and the first valve 3 alternately has an on period for opening the first valve 3 and an off period for closing the first valve 3. It is something to repeat. More specifically, the control mechanism C is a so-called computer provided with a CPU, a memory, an A / D / D / A converter, an input / output means, and the like, and is for a fluid control device 100 stored in the memory. The program is executed, and various devices cooperate with each other to exert at least functions as a pulse signal generator 6, a feedback value calculation unit 7, and a signal correction unit 8.

The pulse signal generator 6 inputs a pulse signal having a predetermined pulse height and a predetermined pulse width to the first valve 3. In the first embodiment, the pulse signal generator 6 is configured to input a voltage pulse signal to the piezo actuator of the first valve 3 at predetermined intervals as shown in FIG. .. That is, while the pulse signal generator 6 is inputting a pulse signal to the first valve 3, the first valve 3 is opened during the on period, which is between the pulse signals and the first valve. While no pulse signal is input to the valve 3, the first valve 3 is closed during the off period. Further, the pulse height of the pulse signal is configured to be sequentially changeable by a correction unit described later, but the pulse width and the period of the pulse signal are fixed. The pulse width is set to, for example, 10 msec order, and the period is set to 100 msec order. The pulse width and the pulse signal period are shown as examples, and may be appropriately set to arbitrary values depending on the intended use.

The feedback value calculation unit 7 calculates, as a feedback value, a time integral value of the amount of pressure drop generated in the internal volume 5 during the on period, based on the pressure value measured by the pressure sensor 2. That is, as shown in the graph of FIG. 4, a pulse signal is input to the first valve 3, and when the first valve 3 is opened, the gas charged in the internal volume 5 is the first valve 3. A pressure drop occurs because the amount of gas having an internal volume of 5 decreases. This pressure drop continues after the input of the pulse signal is started and the first valve 3 is opened until the input of the pulse signal is completed and the first valve 3 is closed. In the first embodiment, the feedback value is an area corresponding to the hatched portion in the graph of FIG. 4, and for example, the time integral value of this pressure drop amount is calculated by the segmented quadrature method.

More specifically, the feedback value calculation unit 7 is based on a pressure value storage unit 71 that sequentially stores the pressure value measured by the pressure sensor 2 and a pressure value stored in the pressure value storage unit 71. Therefore, it is provided with an integrated value calculation unit 72 for calculating the time integrated value of the pressure drop amount.

The pressure value storage unit 71 stores, for example, time-series data of the pressure value from the time when the pulse signal is input to the first valve 3 by the pulse signal generator 6 to the time when the pulse signal ends.

The integrated value calculation unit 72 calculates the time integrated value of the pressure drop amount based on the time series data of the pressure value stored in the pressure value storage unit 71. For example, the integral value calculation unit 72 multiplies the difference between the initial pressure value at the time when the pulse signal is input to the first valve 3 and the pressure value measured at each time point by the sampling time, and divides the quadrature method. The area of the hatched portion in FIG. 4 is calculated by the above method and output as a feedback value.

The signal correction unit 8 corrects the pulse signal input from the pulse signal generator 6 to the first valve 3 after the feedback value is calculated based on the deviation between the feedback value and the reference value. .. More specifically, the signal correction unit 8 is provided so that the deviation between the feedback value calculated from the pressure drop when a certain pulse signal is input to the first valve 3 and the reference value becomes small. Corrects the pulse height of the pulse signal input next to the pulse signal. At this time, the signal correction unit 8 changes the pulse height of the pulse signal to be output next time by changing the setting of the pulse signal generator 6. That is, the pulse height of the pulse signal output from the pulse signal generator 6 by the signal correction unit 8 is sequentially corrected by the time integration value of the pressure drop amount obtained by the pulse signal input one time before. Will be.

Here, the reference value is a predetermined value, and is an actual value of a time integral value of the pressure drop amount when the flow rate of the fluid passing through the first valve 3 becomes the target flow rate. That is, the time integral value of the pressure drop amount corresponding to the target flow rate to be flowed to the film forming chamber CH in one on period is used as a reference value and obtained in advance by an experiment or the like.

<Operation of the first embodiment>
Next, the operation related to the pulse control of the flow rate by the fluid control device 100 of the first embodiment will be described with reference to the flowchart of FIG.

First, the fluid control device 100 starts flow rate control by pulse control from a state in which the internal volume 5 is charged with a gas having a sufficient pressure. That is, the pulse signal generator 6 inputs a pulse signal to the first valve 3 with the default pulse height and pulse width (step S1).

The first valve 3 is opened for a predetermined time corresponding to the pulse width of the pulse signal (step S2). While the first valve 3 is open, the gas charged in the internal volume 5 flows through the first valve 3 to the film forming chamber CH. Therefore, the pressure of the gas at the internal volume 5 continues to decrease during the on period as shown in the graph of FIG. 4 (step S3). When the input of the pulse signal to the first valve 3 is completed, the state in which the first valve 3 is closed is maintained for a predetermined time (step S4). While the first valve 3 is closed, new gas passes through the resistor 1 from the upstream side and is charged into the internal volume 5, and the pressure of the gas rises (step S5). ..

In parallel with steps S2 to S7, the feedback value calculation unit 7 calculates as a feedback value the time integral value of the pressure drop amount during the on period from the opening of the first valve 3 to the closing of the first valve 3. (Step S6). After that, the signal correction unit 8 corrects the pulse height of the pulse signal next output from the pulse signal generator 6 based on the deviation between the feedback value and the reference value (step S7). For example, when the feedback value is smaller than the reference value, the pulse height is changed to be higher than the previous time because the flow rate is insufficient. On the contrary, when the feedback value is larger than the reference value, the flow rate is excessive and the pulse height is changed to be lower than the previous time.

Next, the pulse signal generator 6 determines whether or not a predetermined number of pulse signals have been output (step S8), and if the pulse signal generator 6 has not yet reached the predetermined number, the pulse signal generator 6 is corrected in step S8. A pulse signal having a pulse height is input to the first valve 3 with the same pulse width as the previous time (step S9).

After that, the operations of steps S2 to S10 are repeated until a specified number of pulse signals are input to the first valve 3. After all the cycles are completed, the operation of the flow system device is terminated.

<Effect of the first embodiment>
According to the fluid control device 100 of the first embodiment configured in this way, the pulse height of the pulse signal input to the first valve 3 is set by using the time integrated value of the pressure drop amount during the on period as the feedback value. Since the correction is made sequentially, the flow rate of the gas passing through the first valve 3 can be kept uniform at the target flow rate during each on period.

More specifically, as shown in the graph of FIG. 6, the pressure drop amount as in the first embodiment is compared with the case where the opening degree of the first valve 3 is fed back and pulse controlled as in the conventional case. When the pulse control is performed by feeding back the time integral value of, the linearity between the fed back value and the actual flow rate can be improved as compared with the conventional case. Therefore, the control accuracy of the actual flow rate can be further improved as compared with the case where the opening degree is actually measured and fed back as in the conventional case.

Based on these facts, the flow rate of each gas that passes through the first valve 3 and flows into the film forming chamber CH by each pulse signal is adjusted to an amount necessary and sufficient for forming a film for, for example, one atom. It is possible to realize high quality film formation in ALD.

Further, since the signal correction unit 8 changes only the pulse height to adjust the flow rate of the flowing gas in the state where the first valve 3 is open, and the pulse width and period are fixed, for example, a large number. Even when the cycle is carried out and the gas is introduced into the film forming chamber CH, the time taken from the start to the end does not change. That is, it is possible to maintain high productivity without changing the process time while improving the accuracy of the flow rate of the recipe set in ALD.

<Structure of the second embodiment>
Next, the fluid control device 100 according to the second embodiment of the present invention will be described with reference to FIGS. 7 and 8.

In the fluid control device 100 of the second embodiment, as compared with the first embodiment, the resistor 1 is the second valve 1, and the control mechanism C controls the second valve 1. The difference is that it has a 9. Specifically, in the second embodiment, the flow path resistance to the inflowing fluid with respect to the internal volume 5 can be adjusted by changing the opening degree of the second valve 1.

Similar to the first valve 3, the second valve 1 is configured to drive the valve body by a piezo actuator so that the opening degree, which is the position of the valve body with respect to the valve seat, can be changed.

The second valve control unit 9 controls the opening degree of the second valve 1 based on the pressure value of the gas in the internal volume 5 measured by the pressure sensor 2. Specifically, the voltage applied to the second valve 1 is controlled so that the deviation between the pressure value measured by the pressure sensor 2 and the preset pressure value becomes small. Here, the set pressure value is a pressure value that the internal volume 5 should maintain at the time when a pulse signal is input to the first valve 3 to open the first valve 3 in order to realize the target flow rate. In the second embodiment, by controlling the second valve 1, the same pressure is charged to the internal volume 5 at least immediately before the first valve 3 is opened.

<Operation of the second embodiment>
As shown in the flowchart of FIG. 8, the fluid control device 100 of the second embodiment performs the same operations as the fluid control device 100 of the first embodiment from steps S1 to S9, but is in a state before executing step S1. From to the completion of all cycles, the opening control by pressure feedback is continued so that the pressure value measured by the pressure sensor 2 in the second valve 1 becomes the set pressure value (step S0). ).

<Effect of the second embodiment>
In the fluid control device 100 configured as described above, the pressure of the gas in the internal volume 5 is applied by the second valve 1 before the pulse signal is input to the first valve 3 to carry out the on period. Since the set pressure value is maintained, the differential pressure before and after the first valve 3 can always be kept constant at the start of each on period. Therefore, since the physical quantity other than the pulse height, which is not a control target, can be kept constant, the control accuracy of the flow rate of the gas passing through the first valve 3 in each cycle can be further improved.

Next, the fluid control device 100 according to the third embodiment of the present invention will be described with reference to FIGS. 9 and 10.

In the fluid control device 100 of the third embodiment, as compared with the second embodiment, the first valve 3 does not feed back the time integrated value of the pressure drop amount, but the actual opening degree measured by the displacement sensor 4. The difference is that it is controlled by feeding back.

More specifically, the feedback value calculation unit 7 in the first and second embodiments is omitted in the control mechanism C of the third embodiment.

Further, the signal correction unit 8 further determines the pulse of the pulse signal output from the pulse signal generator 6 based on the deviation between the actual opening degree measured by the displacement sensor 4 and the preset opening degree. It is configured to correct the height. Specifically, the signal correction unit 8 measures the opening degree of the first valve 3 when a certain pulse signal is output by the displacement sensor 4, and the next pulse is based on the actual opening degree. The setting of the pulse signal generator 6 is changed so that the pulse height of the signal approaches the set opening degree.

The set opening degree is an actual value of the opening degree required for flowing the target flow rate in a state where the upstream side of the first valve 3 is kept at the set pressure and the downstream side is kept in a substantially vacuum, for example.

<Operation of the fluid control device 100 of the third embodiment>
The operation of the fluid control device 100 of the third embodiment is different from the operation of the fluid control device 100 of the second embodiment shown in FIG. 8 only in the operations of steps S6 and S7. That is, in the fluid control device 100 of the third embodiment, the opening degree realized by the first valve 3 during the on period is actually measured by the displacement sensor 4 (step S6'), and the actual opening degree and the set opening degree are measured. The correction amount of the pulse height of the pulse signal to be output next time is changed based on. (Step S7')

<Operation of the fluid control device 100 of the third embodiment>
In the fluid control device 100 of the third embodiment configured in this way, since the pressure of the internal volume 5 is maintained at the set pressure by the second valve 1, the first valve is provided by the opening feedback. Even if 3 is pulse-controlled, the flow rate control accuracy can be improved as compared with the conventional case.

In addition, it is not necessary to perform calculations such as integration to calculate the feedback value, and since the calculation load is small, there is sufficient margin even when the pulse width and period are short and the time required for calculation is short. Opening feedback is possible. That is, the flow rate can be controlled with high accuracy in each cycle without using a high-speed CPU or the like in the control mechanism C.

Further, since the second valve 1 is controlled so that the gas pressure in the internal volume 5 is kept constant, even if there is a fluctuation in the gas pressure on the upstream side of the second valve 1. Such fluctuations can have almost no effect on the control accuracy of the flow rate of the gas passing through the first valve 3. That is, the robustness of the flow rate control can be enhanced. In addition, since linearity between the opening degree and the flow rate can be realized for a wide flow rate range, it is possible to accurately realize the flow rate control in a wide range by identifying only one calibration curve, for example.

Other embodiments will be described.
In each embodiment, the pulse height of the pulse signal is corrected so that the flow rate of the fluid passing through the first valve is kept constant in each cycle. However, for example, the pulse width of the pulse signal is corrected. By doing so, the flow rate may be controlled. Further, the flow rate in each cycle may be kept constant by correcting both the pulse height and the pulse width.

The reference value used in the signal correction unit is not predetermined, but may be set by using several pulses after the start of pulse control as adjustment pulses. Specifically, the reference value may be a value when the time integral value of the pressure drop amount actually measured in several pulses after the start of pulse control becomes a value corresponding to the target flow rate. In addition, if the time integrated value of the pressure drop amount is fed back only in a few pulses at the start of pulse control and the integrated value of the same time drop amount as the reference value can be realized, the same applies thereafter without operating the signal correction unit. It may be continued to operate at the pulse height and the pulse width.

In the above embodiment, the signal correction unit corrects the pulse height or the pulse width based on the integrated value of the pressure drop amount generated in the on period due to the pulse signal output immediately before a certain pulse signal. However, for example, the pulse signal currently output may be corrected based on the integrated value of the amount of pressure drop generated in the on period due to the pulse signal output two or three times before. Further, the pulse height or pulse width of the pulse signal may be corrected during the same on period based on the integrated value of the pressure drop amount generated in the on period due to a certain pulse signal. For example, based on the integrated value of the pressure drop obtained in the first half of the on period, it may be compared with the reference value and corrected for the pulse signal in the second half of the on period. Further, for example, the pulse height of the pulse signal may be sequentially changed while sequentially calculating the integrated value of the pressure drop amount.

The fluid control device does not control the flow rate of the fluid passing through the first valve, but may control the pressure.

The fluid control device according to the present invention may be used not only for ALD but also for pulse supply of fluid in various applications.

The first valve and the second valve are not limited to those using a piezo actuator, and may be those in which the valve body is driven by various actuators such as a solenoid.

The resistor may be any as long as it forms a flow path resistance, and is not limited to the one described in each embodiment.

The method of calculating the time integral value of the pressure drop amount is not limited to the segmented quadrature method, and may be calculated by various methods. For example, the area of the triangular region may be used as an approximation of the time integral of the pressure drop, based only on the pressure values at the start and end points of the on period.

In addition, various combinations and modifications of the embodiments may be performed as long as they do not contradict the gist of the present invention.

100 ... Fluid control device 1 ... Resistor (second valve)
2 ・ ・ ・ Pressure sensor 3 ・ ・ ・ First valve 4 ・ ・ ・ Displacement sensor 5 ・ ・ ・ Internal volume 6 ・ ・ ・ Pulse signal generator 7 ・ ・ ・ Feedback value calculation unit 71 ・ ・ ・ Pressure value storage unit 72・ ・ ・ Integral value calculation unit 8 ・ ・ ・ Signal correction unit 9 ・ ・ ・ Second valve control unit

Claims (8)

A resistor provided in the flow path through which the fluid flows, and
A first valve provided on the downstream side of the resistor in the flow path,
A pressure sensor provided between the resistor and the first valve in the flow path and measuring the pressure of the fluid in the internal volume between the resistor and the first valve.
A control mechanism for controlling the first valve is provided.
The control mechanism
A pulse signal generator that inputs a pulse signal having a predetermined pulse height and a predetermined pulse width to the first valve.
Based on the pressure value measured by the pressure sensor, the feedback value calculation unit calculates the time integral value of the pressure drop amount generated in the internal volume during the on period when the first valve is open as the feedback value.
A fluid control device including a signal correction unit that corrects a pulse signal input from the pulse signal generator to the first valve based on a deviation between the feedback value and a reference value. The fluid control device according to claim 1, wherein the reference value is an actual value of a time integral value of a pressure drop amount when the flow rate of the fluid passing through the first valve becomes a target flow rate. The first or second aspect of claim 1 or 2, wherein the signal correction unit is configured to change the pulse height while keeping the pulse width of the pulse signal constant so that the deviation between the feedback value and the reference value becomes small. Fluid control device. The first or second aspect of claim 1 or 2, wherein the signal correction unit is configured to change the pulse width while keeping the pulse height of the pulse signal constant so that the deviation between the feedback value and the reference value becomes small. Fluid control device. The resistor is a second valve whose opening degree can be controlled.
The control mechanism
A claim further comprising a second valve control unit that controls the second valve so that the deviation between the pressure value measured by the pressure sensor and the set pressure value becomes small during the off period when the first valve is closed. Item 4. The fluid control device according to any one of Items 1 to 4. The fluid control device according to any one of claims 1 to 5, wherein the first valve further includes a displacement sensor for measuring the opening degree thereof. A resistor provided in the flow path through which the fluid flows, a first valve provided in the flow path on the downstream side of the resistor, and provided between the resistor and the first valve in the flow path. A fluid control method using a fluid control device comprising a pressure sensor for measuring the pressure of the fluid in the internal volume between the resistor and the first valve.
A control step for controlling the first valve is provided.
The control step
A pulse signal generation step of inputting a pulse signal having a predetermined pulse height and a predetermined pulse width to the first valve, and a pulse signal generation step.
Based on the pressure value measured by the pressure sensor, a feedback step of calculating the time integral value of the pressure drop amount generated in the internal volume during the on period when the first valve is opened as a feedback value, and a feedback step.
A fluid control method comprising: a signal correction step for correcting a pulse signal input to the first valve based on a deviation between the feedback value and a reference value. A resistor provided in the flow path through which the fluid flows, a first valve provided in the flow path on the downstream side of the resistor, and provided between the resistor and the first valve in the flow path. It comprises a pressure sensor for measuring the pressure of the fluid in the internal volume between the resistor and the first valve, and a control mechanism for controlling the first valve, wherein the control mechanism is a computer and the first valve. A fluid control program used in a fluid control device including a pulse signal generator for inputting a pulse signal having a predetermined pulse height and a predetermined pulse width for one valve.
A feedback value calculation unit that calculates the time integral value of the pressure drop amount generated in the internal volume during the on period when the first valve is opened as a feedback value based on the pressure value measured by the pressure sensor.
For a fluid control device that causes a computer to function as a signal correction unit that corrects a pulse signal input from the pulse signal generator to the first valve based on the deviation between the feedback value and the reference value. program.

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